I have a not-null char(1) field that can be 'U' or some other value. I
also have a stored procedure, that among other things needs to select
items based on a char(1) parameter.

The pseudo-SQL is:
Select * from table where (Field in ('U') and :param in ('U')) or (Field
not in ('U') and :param not in ('U'))

Parameter tests aren't legal to the planner ( 'Z' not in ('U') ), and I
can't branch to execute one query or another. Any ideas for a
conditional statement for the WHERE clause?

Thanks, Rick DeBay